Railway traffic controlling apparatus



. 1.940- E. M. ALLEN RAIILJWY TRAFFIC CONTROLLING APARATUS Oct.

Filed July 22. 1939 www u INVENTOR- HIS ATTRNEY Patented Oct. 1, 1940 UNITED STATES vRAILWAY TRAFFIC CONTROLLING APPARATUS Earl M. Allen, Swissvale, Paf, assignor to The 'y Union Switch & Signal Company, Swssvale, K Pa., a corporation of Pennsylvania Application July 22, 1939, serial No. 286,012

6 claims. (o1. 246-161) switch.

More specically, my invention relates to the release of approach and stick locking for a switch. One feature of my invention is the provision of novel and improved means for providing a short release period for the locking for low speed routes, while a longer release period is provided for the locking for higher speed routes.

I shall describe one form of apparatus embodying my invention, and shall then point out the novel features thereof in claims.

The accompanying drawing is a diagrammatic view showing one form of apparatus embodying my invention;

Referring to the drawing, the reference characters 3 and 3a designate the track rails of a stretch of main railway track divided by insulated joints 4 to forma main section IT, a first approach section D2T, and a second approach section AD2T. Each track section is provided with a track circuit including a track battery 5 connected across the rails adjacent one end of the section, and a track relay, designated by the reference character R preceded by the reference character for the associated section, connected across the rails adjacent the opposite end of the section.

, A track switch I is included in section IT for connecting the main track with an auxiliary track X. Switch I is provided with an operating mechanism `M which as here shown is controlled by a polarized switch control relay WR.

Traffic moving toward the right as shown in the drawing, which I shall assume is the eastbound direction, is governed by a iirst signal ZRA for the main track, andby a second signal 2RB for the auxiliary track X. Signals 2RA and 2R13 are 'controlled by `signal control means here shown as iirst and second signal relays ZRAI-IR and 2RBI-IR, respectively. A distant signal D2 controls eastbound traine movements on the main track through section DZT toward signal 2RA. The caution or 45. position of signal D2 is controlled by track relay D2TR, and the proceed or 90 position of,v this signal is controlled by a distant control relay DZDR. As shown in the drawing, the signals are of the semaphore type, but may be of any other suitable design.

The contacts operated by the various relays, by switch I, and by the time element device 2RTER are identied by numbers, each such number having a distinguishing prefix from which it is separated by a dashwhenthe associated contact is shown apart from the relay or :other device by which it is operated. `The prex for each of these contact numbers comprisethe reference character for the relayy or other device by which the associated contact is' operated... For example, contact ZRTESRf-ZZ, in the portion of the control circuits shown for relays. ZRAHR and ZRBHR, is identiied by the number 22 which is PATENT f oErICE Y separated by a dash from the prex 2RTESR which is the reference character for relay ZRTESR by which this contact is operated.

An approach and stick locking relay designated by the reference character ZRASR controls, in part, the switch control relay WR by means of a front contact 2RASRf-6, so that relay WR cannot be energized for effecting operation of switch I unless relay ZRASR is energized. Only a portion of the normal and reverse control circuits for relay WR is shown inthe drawing, land the portions of these circuits which are' not shown may be controlled in any suitable manner, such for example as by a lever operated by a leverman in an interlocking tower.

Energization of locking relay ZRASR isv controlled in part by time element means here shown as a thermal device ZRTER, by a first slow release auxiliary stick relay 2RTESR,v and by a second auxiliary stick relay 2RTEPSR. 'Iime lelement means or device ZRTER operates a first time contact ZRTER-I I which is normally closed, and which opens in response to energization of device ZRTER, and which is slowly closed when device ZRTER becomes deenergized. Device ZRTER also operates a second normally open time contact 2l which is slow to close when device ZRTER becomes energized, and which is slow to open in response to deenergization of device ZRTER. u

`Contacts I2 and I6 are operated in conjunction with switch I, so that contact I2 is closed only when switch I occupies the normal position, and contact I6 is'closed only when switch I occupies the reverse position.

Only a portion. of the control circuitsl for relays 2RAHR and ZRBHR is shown in the drawing. The portions not shown may be controlled in any suitable manner, such for example as by a lever operated by a leverman in an interlocking tower. Relay ZRAI-IR may also be controlled by a front contact of relay ITR.

Having described, in general, the arrangement and control of the apparatus, I shall now describe, in detail, its o-peration.

As shown in the drawing, all parts are in the normal condition, that is, switch I is in its normal position; signals 2RA and ZRB are indicating stop; signal D2 is indicating caution; switch control relay WR is energized; track relays I'I'R, DZTR and AD2'IR are energized; locking relay ZRASR is energized; and relays ZRAHR, ZRBHR. DZDR, 'ZRTESR and ZRTEPSR, and time element device ZRTER are deenergized.

With track relay D2'I'R energized, signal D2 is retained in the 45 position by a circuit passing from terminal B of a suitable source of current, through contact 'I of relay DZTR, and the mechanism of signal D2 to terminal C of the same source of current.

Both a pick-up and a stick circuit are closed for locking relay ZRASR, the pick-up circuit passing from terminal B through contacts 8, 9 and I0 of relays DZDR, ZRAI-IR and ZRBI-IR, respective- 1y, contact ZRTER-II, contact I2 of switch I, contacts `ADZTR--IS and D2'IR-I4, and the winding of relay ZRASR toterminal C. The stick circuit is the same as the pick-up circuit just traced as farl as Contact III of relay ZRBI-IR, and theny passes through the front point of contact I9 of relay ZRASR, and the winding of relay ZRASR to terminal C.

I shall assume .that the leverman desires t0 arrange for an eastbound train to move over the main line with switch I in its normal position.

As shown in the drawing, switch I is in its normal position, and the leverman has therefore only to clear Y.signal ZRA byl `energizing relay 2RAHR. Relay 2RAI-IR, upon becoming energized, completes a circuit for operating the arm of signal v2BA to a position for directing traic movements over switch I in the normal position, this circuit passing from terminal B, through contact 24 of relay ZRAHR, and the mechanism of signal ZRA to terminal C. VWith relay ZRAI-IR,

energized, relay D2DR becomes energized by its circuit passing from terminal `B through contact 25 of relay ZRAI-IR, and the Winding of relay DZDR to terminal C. With relay DZDR energized, the arm of signal D2 will be operated to the 90 position by a circuit passing from terminal B, through contact 'I of relay DZTR, contact 2i of relay D2DR, and the mechanism of signal D2 to terminal C. 'Relays 2RAI-IR and D2DR, upon becoming energized, open the pick-up and stick circuits for relay ZRASR at contacts 9 and 8, respectively. I

If now the eastbound train moves through section ADET and enters section D2T, contact 'l of relay DZTR will open, thereby causing the arm of signal D2 to move to the stop position., If, when the train enters section IT relay ZRAHR becomes d'eenergiz'ed due to the deenergization of relay. I'IR, cr if the leverman manually opens the circuit for relay ZRAHR, contact 24 of relay ZRAI-IR will vopen the circuit previously traced for signal ZRA, causing the arm of this signal to also move to the 4stop position.

With the trainin section I'I, a second pick-up circuit is completed forrelay ZRASR, which is the same as the pick-up circuit previously traced as vfar as conta-ct 2RTER-II, and then passes through contact ITR-Iil,A and the winding of relay 2RASR to terminal C'. When the train leaves section D2'I, relay DZTR again becomes energized and completes the pick-up circuit rst traced for relay ZRASR.

I shall now assume that the leverman again clears signal 2RA`foran eastbound train to pro# ceed on the main track over switch I in its normal position, and that after the train enters section ADEBT, the leverman returns the arm oi signal ERA. to the stop position by deenergizing relay RAHR, and thereby also deenergizes relay DDR. With relay ZRASR remaining deenergized on account of its rst pick-up circuit being open at contact AD2'I'R-I3 and its second pickup circuit being open at contact I'IR--I8, and with `relays 2RAHR and DZDR again deenergized, an energizing circuit for the time element device ERTER is completed, passing from terminal B, through contacts 8, 9 and ID of relays DEDR, ZRAHR and ZRBHR, respectively, back point of contactl i9 of relay RRASR, back point of contactJ 2li oi relay ZRTESR, and the control element oi device RTER to terminal C.

Contactl 2l of device ZRTER, which is slow in picking up, completes a pick-up circuit for relay 2RTESR upon the lapse of a measured period of time, which is the same as the energizing circuit for device ZR'IER as far as Contact I0 of relay ZRBHR, and then passes through contact 2i of device ERTER, and the winding of relay ZRTESR to terminal C. A stick circuit for relay RTESR is then closed, which is the same as the pick-up circuit for this relay as far a-s contact lil of relay ZRBI-IR, and then passes through the back point of contact I9 of relay ZRASR, front point oi contact 2i) of relay 2RTESR, and the winding of relay ZRTESR to terminal C. With relay 2R'IE`SR energized, the energizing circuit for device ZRTER is opened at the back point of contact 21B of relay ZRTESR. Contact RTER-II, which is slow to close, will complete a third pick-up circuit for relay ZRASR after the lapse of a further periodl of time, this circuit being the same as the second pick-up circuit previously traced as far as contact 2RTER i I, and then passing through contact 2R'I'ESR il, and the winding of relay ZRASR to terminal C.

It follows that, under the procedure just outlined, the locking Arelease period is the time required for the third pick-up circuit for relay ZRASR to become closed after the leverman dei energizes relay ZRAI-IR, and includes both the pick-up time for device ZRTER, through its contact 2l, and the release time for device ZRTER, through its contact 2RTER-I I.

I shall next assume that there is a train on auxiliary track X, and that the leverman desires to permit this train to pass over switch I in the reverse position to the main line. With relay ZRASR energized, the leverman can supply cur-'- rent of reverse polarity to relay WR through contact 2RASR--E, causing the polar contact of relay WR to close in the reverse position, and thereby completing the reverse operating circuit for mechanism M for switch I, this circuit passing from terminal B, through contact 2l of relay WR, contact 28 of relay WR closed in its righthand or reverse position, and mechanism M to terminal C. With relay ZRTESR deenergized on account of relay ZRASR having become energized, the leverman will `now energize relay ZRBHR by its circuit which includes contact 2R'IESR-22- The arm of signal -.2RB will then be operated to the position for directing traflic movements over switch I in thereverse position, by its circuit passing from terminal B, through contact 23 of relay ZRBI-Ht, and the mechanism of signal ZRB to terminal C. With relay ZRBHR energized, the pick-up and stick circuits for relay ZRASR, will be opened at contact I0 of relay ZRBHR, causing relay ZRASR to become deenergized. I

I shall further assume that the leverman now decides to hold the train 0n track X, instead of permitting it to proceed past signal 2RB. I-Ie will therefore deenergize relay ZRBHR, thus causing the arm of signal 2RB toreturn to its stop position.

The energizing circuit previously traced for device ZR'IER will now again close. Before contact ZR'I'ER-I I opens, however, a pick-up circuit is completed for relay ZR'IEPSR, passing from terminal B, through contacts 8, 9 and I0 of relays DZDR, ZRAI-IR and 2RBHZR., respectively, contact ZRTERf-I I, contact I6 of switch I, and the Winding of relay ZRTEPSR to terminal C. Relay ZRTEPSR, upon becoming energized, completes its stick circuit which is the same as the pick-up circuit just traced as far as contact I0 of relay ZRBI-IR., and then passes through contact I5 of relay ZRTEPSR, contact I6 of switch I, and the winding of relay ZR'I'EPSR to terminal C.

As soon as relay 2RTESR becomes energized by its pick-up circuit p-reviously traced, a fourth pick-up circuit will now be completed for relay ZRASR, which is the same as the pick-up circuits previously traced for this relay as far as contact Ill of relay ZRBI-IR., and then passes through contact I5 of relay ZRTEPSR, contact 2RT'ESR- Il, and the winding of relay ZRASR to terminal C. Relay ZRASR, therefore, now becomes energized after the closing period of contact 2I only, instead of having to wait through both the closing period of contact 2| and the subsequent closing period of contact ZRTER-I I asin the case of the third pick-up circuit traced for relay ZRASR.

I shall now assume that all parts of the apparatus are again returned to the normal condition, and that the leverman again reverses switch I and clears signal ZRB. I shall further assume that the leverman then again returns the arm of signal 2RB to the stop position before a train passes this signal, and thereby again starts the operation of time element device ZRTER. I shall also further assume that the leverman then again clears the arm of signal ZRB and that again, before a train passes this signal, he returns the arm of signal ZRB to the stop position.

I shall also assume that contact ZRTERf-II is already open when the leverman returns the arm of signal 2RB to the stop position the second time, because of his having returned this signal to stop the iirst time. Relay ZRTEPSR, will therefore not now be energized, on account of contact ZR'IER-II being open. The energizing circuit for device ZR'I'ER will, however, now be closed, causing this device to close its contact 2I and energize relay ZRTESR. On account of device 2RTER being now energized before being returned to the normal condition following its previous energization, the time required for closing its contact 2 I` will be less than the time usually required for this contact to close. However, on account of relay 2RTEPSR being deenergized, relay ZRASR cannot now become energized until contact 2RTER-I l has again closed and completed the third pick-up circuit for relay ZRASR., whereas in the usual operation when the leverman returns the arrn of signal ZRB to the stop position before a train passes this signal, the release period for relay 2RASR. includes only the pick-up time of contact 2l of device ZRTER and the pick-up time of relay ZRTESR.

It follows that the locking relaseperiod, when the leverman returns the'armof signal ZRB to' the stop'position and'then again clears the signal and almost immediately again returns the arm of signal 2RBfto the stop position, includes part of the lclosing period for contact 2l of device ZRTER when device 2R'IER becomes energized, and also includes the closing'period for contact 2RTER-II when device 2RTER becomes deenergized. r I

I shall next'assume that the leverman again twice clears the arm of signal ZRB and then returns it to the stop positiona's before, but that contact 20 of relay ZR'I'ESR lbecomes closed immediately at its front point, as well as contact ZR'IER-II being already'open, when the leverman returns the arm of signal 2RB tothe stop position the second time. `With relayZRTESR energized, device ZRTER is deenergized, and hence the third pick-up circuit for relay ZRASR will now become closed after only the time required for contact ZRTER-II to become closed.

From the foregoing description 'and the accompanying drawing, it follows that in lapparatus embodying my invention, I have employed means for providing a short release period for the switch locking for a low speed route and for providing a longer release period for a higher speed route.

In the means which I have employed, if for some reason the thermal time element device is already partially heated when it becomes energized for effecting energization of relay ZRASR for a low speed route, the heating of the device must nrst be completed and then the device must be cooled before the locking for the low speed route is released.

Although I have herein shown and described only one form of apparatus embodying my invention, it is understood that various changes and modications may be made therein within `the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination, a stretch of railway track including a switch, a signal for governing traic movements over said switch when said switch is in the normal position, a second signal for governing traflic movements over said switch when said switch is in the reverse position, an approach locking relay, an auxiliary stick relay, a second auxiliary stick relay, a time element device, first and second signal control means controlled by a back contact of said rst auxiliary stick relay for clearing said iirst and second signals respectively, a pick-up circuit for said approach locking relay controlled by said time element device in the deenergized condition and by said switch in the normal position and closed only if said stretch of track is unoccupied within a given distance in the rear of said rst signal, a second pick-up circuit for said approach locking relay controlled by said time element device in the deenergized condition and by a front contact of said first auxiliary stick relay, a third pick-up circuit for said approach locking relay controlled by frontcontacts of said iirst and second auxiliary stick relays, al pick-up circuit for said second auxiliary stick relay controlled by said time element device in the deenergized condition and by -70 said switch in the reverse position, a stick circuit for said second auxiliary stick relay controlled by said switch in the reverse position, an energizing circuit for said time element device controlled by back contacts of said approach i7f5 locking and first auxiliary stick relays, `a pick-up circuit for said iirst auxiliary stickl relay controlled by said time element device in the energized condition, a stick circuit for said first auxiliary stick relay controlled by a back'contact of said approach locking relay, means controlled by said rst and second signal control means upon becoming energized for opening all the pick-up and stick circuits for said rst and second auxiliary stick relays and for said approach locking relay and for opening the energizing circuit for said time element device, and means controlled by a front contact of said approach locking relay for controlling operation of said switch between its normal and reverse positions.

2. In combination, a stretch of railway track including a switch, a signal for governing traflic movements over said switch when said switch is in the normal position, a second signal for governing traic movements over said switch when said switch is in the reverse position, an approach locking relay, an auxiliary stick relay, a. time element device, a first time contact which becomes opened by said time element device when said time element device becomesv energized and which is slow to close when said time element device becomes deenergized, a second time contact which is slow to be closed by said time element device when said time lelement device becomes energized and which opens in response to deenergization of said time element device, rst and second signal control means controlled by a back contact of said auxiliary stick relay for clearing said rst and second signals respectively, a pick-up circuit for said approach locking relay controlled by said first time contact and by said switch in the normal position and closed only if said stretch of track is unoccupied within a given distance in the rear of said first signal, a second pick-up circuit for said approach locking relay controlled by said rst time contact and by a front contact of said auxiliary stick relay, a circuit for energizing said time element device controlled by back contacts of said approach locking and auxiliary stick relays, a pick-up circuit for said auxiliary stick relay controlled by said second time contact, a stick circuit for said auxiliary stick relay controlled by a back contact of said approach locking relay, means controlled by said first and second signal control means upon becoming energized for opening all the pick-up and stick circuits for said auxiliary stick relay and said approach locking relay and for opening the energizing circuit for said time element device, and means controlled by a front contact of said approach locking relay for controlling operation of said switch between its normal and reverse positions.

` 3. In comb-ination, a stretch of railway track including a switch, a rst and a second signal for governing trafc movements over said switch in its normal and reverse positions respectively, a locking stick relay, a first and a second auxiliary vstick relay, time element means, a first time contact opened by said time element means upon energization of said time element means and which is slow to close upon deenergization of said time element means, a second time contact of said time element means which is slow to close upon energization of said time element means, a pick-up circuit for said locking stick relay controlled by said first time Contact and by a front contact of said first auxiliary stick relay, a stick circuit for said locking stick relay, a circuit for energizing said time element means controlled by back contacts of said locking and first auxiliary stick relays, a pick-up circuit for said rst auxiliary stick relay controlled by said second time contact, a stick circuit 'for said `rst auxiliary stick relay controlled by a back contact of said locking stick relay, a pick-up circuit for said second auxiliary stick relay controlled by said first time contact and by said switch in one of its extreme positions, a stick circuit for said second auxiliary stick relay controlled by said switch in said one extreme position, a second pick-up circuit for said locking stick relay controlled by front contacts of said first and second auxiliary stick relays, means associated with said signals for opening the pick-up and stick circuits -or said locking and auxiliary stick relays and the energizing circuit for said time element means if either of said signals is controlled to direct a traffic movement over said switch, and means controlled by a front contact of said locking stick relay for effecting operations of said switch to its normal and reverse positions.

4. In combination, a stretch of railway track including a switch, a signal for governing traffic movements over said switch, a locking relay, a iirst and a second auxiliary stick relay, time element means, a rst time contact opened by said time element means in response to energization of said time element means and which is slow to close upon deenergization of said time element means, a second time contact controlled by said time element means and which is slow to close upon energization of said time element means, a pick-up circuit for said locking relay controlled by said first time contact and by a iront contact of said first auxiliary stick relay, a stick circuit for said locking relay, a second pick-up circuit for said locking relay controlled by front contacts of said first and second auxiliary stick relays, a circuit for energizing said time element means controlled by back contacts of said locking and first auxiliary stick relays, a pick-up circuit for said rst auxiliary stick relay controlled by said second time contact, a stick circuit Vfor said first auxiliary stick relaycontrolled by a back contact of said locking relay, a pick-up circuit for said second auxiliary stick relay controlled by said first time contact, a stick circuit for said second auxiliary stick relay, means associated with said signal for opening the pick-up and stick circuits for said locking and auxiliary stick relays and the energizing circuit for said time element means if said signal is controlled to direct a traiic movement over said switch, and means controlled by said locking relay for preventing operation of said switch unless said locking relay isenergized.

5. In combination, a stretch of railway track including a switch, a signal for Vgoverning trac movement over said switch, a locking relay, an auxiliary stick relay, time element means, a first time contact opened by said time element means in response to energization of said time element means and which is slow to close upon deenergization of said time element means, a second time contact controlled by said time element means which is slow to close upon energizatiori of said time element means, a normally open release contact, means controlled by said second time contact for closing said release contact, means controlled by a back contact of said locking relay for subsequently maintaining said release contact closed, a pick-up circuit for said locking relay controlled by said first time contact and by said release contact, a second pick-up circuit for said locking relay controlled by said` release contact and by a front contact of said auxiliary stick relay, a stick circuit for said locking relay, a circuit for energizing said time element means controlled by a back contact of said locking relay, a pick-up circuit for said auxiliary stick relay controlled by said rst time contact, a stick circuit for said auxiliary stick relay, means associated with said signal for opening the pickup and stick circuits for said locking and auxiliary stick relays and the energizing circuit for said time element means if said signal is controlled to direct a tranic movement over said switch, and means controlled by said locking relay for pre- Venting operation of said switch unless said locking relay is energized.

6; In combination, a stretch of railway track including a switch, a rst and a second signal for governing traffic movements over said switch in the normal and reverse positions respectively, a locking relay, an auxiliary stick relay, time element means, a first time 'contact opened by said time element means in response to energization of said time element means and which is slow to close upon deenergization of said time element means, a second time contact controlled by said time element means which is slow to close upon energization of said time element means, a pickup vcircuit for said locking relay controlled by said first and second time contacts, a second pick-up circuit for said locking relay controlled by said second time contact and b-y a front contact of said auxiliary stick relay, a stick circuit for said locking relay, a circuit for energizing said time element means controlled by a back Contact of said locking relay, a pick-up circuit for said auxiliary stick relay controlled by said iirst time contact and by said switch in one of its extreme positions, a stick circuit for said auxiliary stick relay, means associated with said signals for opening the pick-up and stick circuits for said locking and auxiliary stick relays and the energizing circuit for said time element means in response to the control of either of said signals to direct a traic movement over said switch, and means controlled by said locking relay for preventing operation of said switch unless said locking relay is energized.

EARL M. ALLEN. 

